Sleep disordered breathing can occur during pregnancy due to the development of hormonal changes and respiratory function abnormalities that perturb patency of the upper airways. Habitual snoring has been described in 25 p. 100 of the women during the third trimester of pregnancy. The incidence of sleep apnea hypopnea syndrome is unknown due to the lack of longitudinal epidemiological data, and results of the main studies are in favor of upper airway resistance syndrome. However, these sleep-related breathing disorders are more frequently associated with maternal and fetal complications such as maternal hypertension, pre eclampsia and intrauterine growth restriction. This article points out the importance of such associations because of the efficacy of continuous positive airway pressure on the regression of these nocturnal respiratory and vascular complications.